A laboratory study on the anaerobic digestion of yeast waste

Master Thesis


Permanent link to this Item
Journal Title
Link to Journal
Journal ISSN
Volume Title

University of Cape Town

This thesis reports the establishment of a new type of internally clarified digester as a means of treating a strong industrial waste. Factors pertaining to both the system and the waste itself were investigated. A batch system was used to determine the susceptibility of the waste chosen, viz. that from the first separator of a local yeast factory, to anaerobic digestion. The reactor-clarifiers were constructed and operated at a wide range of loadings. A constant hydraulic retention time was maintained for each of the digesters and sufficient sludge withdrawn daily to maintain a constant sludge concentration over the range of loadings used. The ability of each of the parameters used to monitor digestion, to predict periods of digester imbalance was investigated. A mathematical model was derived to describe the process and the kinetic parameters related to the anaerobic digestion of yeast waste evaluated. Possible inhibitory substances present in the waste and/or generated during digestion and their influence on the system were investigated.